One of the central paradoxes of textbook authorship in Indigenous languages is that some of those for whom the textbooks are intended find it challenging to read them. Here, through examining cases of Quechua across the Andes in Peru and in Ecuador, we consider the role of orthography in this paradox. Textbook authors must decide on an alphabet for writing textbooks. Yet, the selection of a particular alphabet or changing the alphabet can cause unforeseen difficulties in reading and teaching with the books. Teachers often have experiences with the letters and with reading and writing that are linked to larger-scale questions about what 'the Quechua language' is and how one writes in Quechua. These experiences affect their own and others' interactions with linguistic varieties and with textbooks, playing a significant role in what and how they teach.